A question for the 4 stroke brains trust. Would having the valve timing a tooth out on either the exhaust or more likely the intake cam, cause the engine to return a low compression test. Due to my manual being in Spanglish, the valve timing procedure is vague. I'm getting 65psi compression and bike won't start. Heads been done up and rings and piston were fine last time I rode it. Bike is a 2002 FSE400

The auto de compressor on the exhaust cam will drop the compression figure considerably. But to answer your original question yes incorrect cam timing can make the compression appear lower than the actual specs. If you have access to one a leak down tester is a far more accurate way of measuring engine health and will pin point the exact point of compression loss.